Link chain



Jan, 30, 1940. E A. DENNISON LINK CHAIN Filed April 22, 1939 Patented Jan. 30, 194i) Ernest Arthur Dennison, Longparish, 'Andover, 8 7 England Application April 22, 1939, Serial In Great Britain April 11,

Claims. This invention relates to chains of the jointed link type and more particularly to endless chaintracks for vehicles such as tractors and armoured cars or tanks.

In a known method of chain-track construction, the chain comprises members arranged alternately along the length of the track, with their adjacent edges notched to allow engagement as hinges upon pins extending transversely of the track. These members will hereinafter be designated sole plates" and connecting pieces respectively, in accordance with a recognized nomenclature. The connecting pieces are usually provided 'withspaced teeth or like means to en- 15 gage the driving sprockets.

The present invention has for its main object to provide an improved mode ofconstruction enabling the link-chain member or sole plate to be fabricated from more suitable materials than hitherto, thereby avoiding or reducing the risk of breakage and thus allowing the vehicles. to operate at higher speed.

Another object of the invention is to build up the sole plate of a chain-track by preparing a ridged body or base piece of a length correspond:- ing to the width of the track, slotting out the ridge at intervals in its length, and inserting in these slots or notches a plurality of stamped plates or the like having pairs of holes in register to receive the joint pins, the parts of the sole plate being then secured together by welding, brazing or the like. The stamped plates constitute links to transmit the pull in the endless track, and they can accordingly be made of high tensile or other suitable steel. The bodies or base pieces may be vmade'f'rom mild steel or other tubes, so that the material can be heattreated or case-hardened after the construction of the complete sole plate.

The invention is hereafter more fully described in connection with the sole plates of chain tracks for vehicles, and with reference to the accompanying drawing, in which Fig. 1 represents a steel tube in the first stage of manufacturing the improved sole plate.

Fig. 2 shows a pair of such tubes assembled together, and Fig. 3 shows a further stage of the manufacture.

Fig. 4 shows the assembled tubes reduced to the ridged body or base piece for the sole-plate; Fig. 5 shows this bodyslotted transversely of the ridge.

Fig. 6 shows two of the several stamped plates employed in making up the sole plate.

Fig. 7 shows the finished sole-plate; Fig. 8

shows the sole plate hinged on one side to an adjacent connecting piece, and ready for hinged engagement with a corresponding connecting piece on the other side.

Figs. 9 and 10 illustrate two modifications hereafter described.

In the preferred method of construction illustrated, each sole-plate is formed by welding together a pair of steel tubes such as a, Fig. 1, having flat surfaces bmachined along the areas which are to be in contact; after assembly, as illustrated in Fig. 2, with the two tubes welded together at c c and along the faces b, the double tubular block is machined to produce another flat surface e extending along its length, transversely and also perpendicularly to the welded facesb, the metal being removed until the thickness at the top of the tubes is reduced almost to nil, as shown in Fig. .3. The block is then split longitudinally along the-lower sides of the tubes at the. points 1, by means of a pair of slitting Saws 9, so that the outer side portions h of the tubes canberemoved by tearing-away the thin connecting films at'the top of the block; alternatively, the longitudinalslitting at the points 1 may be performed before machining the fiatsurface e, and the latter operation carried down to a level which breaks through the interior surfaces of the tubes, so that the outer side portions it will fall clear as the top out is finished. In either case, there is left a body or base-piece i (Fig. 4), of which the cross section is approximately the shape ofthe inverted letter T, but with part-circular concave side faces 7', representing the interior of the original tubes a. The ridge is of this base-piece, representing the=flat topped stem of the inverted T-shape, is then machined out by cutting a plurality of transverse notches or slots 1 at intervals in its length, for example six slots as shown in Fig. 5, for a depth equivalent to about three-quarters of the bore of the original tubes, the spacing of these slots Z corresponding to the notches in the sides of the connecting pieces with which the sole plate is to be associated.

A corresponding number of links m (Fig. 6), which may be stampings of high tensile steel, are alsoprepared to fit the slots Z inthe ridged body or base-piece, these links being of thickness equivalent to the width of the slots 1, and

shaped like oval links with two holes 12. to receive the hinge pins of the track, but having their spaced apart at substantially the same distance as the axes of the tubes a forming the body. The opposite ends of the links may be machined concentric with these holes 12, parts 11 of the semicircular ends being machined to a radius somewhat less than that of the tubes, so that these ends become tangential to the upper edges 1' of the links, which are substantially flush with the surface e; the parts 5 destined to seat in the bottom of the concave faces 7', representing the bores of the original tubes are left of appropriate radius for this purpose, as shown in Figs. 6 and 7.

For assembling the parts of the composite sole plate, the stamped or other links m to be inserted in the cross slots 1 of the body ridge It may be threaded loosely upon the rods t (Fig. 6) of the same diameter as the hinge-pins u, (Fig. 8), and then pressed into place in their respective slots, the rods t holding the links in alignment. The parts can then be welded together at the tops of the links or stampings m and at their opposite edges, and also along the seatings where the links rest on the concave surfaces 7', the latter welds being particularly important and accessible in the case of the links at the ends of the sole plate.

Fig. 8 shows the sole plate partly connected in an endless track, and it will be noted that the pull exerted by the hinge pins it upon the sole plate will be supported by the solid metal of the links m fitted into the slotted ridge 7c, and that the body forms a stiff support or carrier for these links, ensuring their rigidity so that the hinges operate freely.

Instead of preparing the body or base-piece from two parallel tubes a fitted side by side as above described, like the barrels in a double-barrelled gun, there may be substituted the halves of a dividedtube as illustrated in Fig. 9; the tube a is here provided with two parallel flat surfaces b on opposite sides-and is then slit longitudinally at two points in asymmetrical relation to the flat faces, after which the two halves are placed backto back, welded together as described with reference to Fig. 2, and machined to produce the fiat'surface eat the topof the ridge. Again, the body or base-piece may be prepared from a single tube 0., provided with two fiat surfaces 17 intersecting at about -degrees, the tube being then split at a point in its circumference diametrically-opposite tothe intersection of the fiat faces and opened out to bring the two halves back to back, the welding, machining and subsequent operations beingsubstantially as-above described.

What I claim is:

1. In the manufacture of link chains, the method of fabricating a link-chain member by the steps of securing a pair of metal tubes side by side, removing corresponding portions of both tubes to produce a curvilinear T-shaped crosssection, slotting said tubes transversely at inter vals along the stem-portion of said T-shaped cross-section, inserting'a plurality of link plates in said slotted stem-portion, and securing said link, plates in registering positions.

2. In the manufacture :of link chains,

method of frabricating a link-chain member by 1 the steps of securing a pair of metal tubes side byside, removing opposite and corresponding portions of both tubes to produce a body of curvilinear T--shaped cross-section, slotting said method of fabricating a link-chain member by preparing from metal tube material a ridged body with concave side faces of a length substantially equal to the width of the chain, slotting out said body at intervals along and transversely of the ridge, and securing in the slotted ridge and concave side faces a plurality of link-joint plates.

4. In the manufacture of link chains, the

method of fabricating a link-chain member by f splitting a metal tube longitudinally, opening out said tube so as to bring the two halves back to back, shaping the opened-out tube to produce a curvilinear. T-shaped cross-section, slotting said tube at intervals along the-stem-portion of the 1 T-shaped cross-section, and securing in said tube a plurality of link-joint plates, each of said plates extending transversely of the lengthof said tube. v

the steps of assembling a; pair of steel tubes side by side, each ofisaid tubes having a flat on its outersurfaceand the two flats being in contact,

welding said assembled tubes together, slitting said tubes longitudinally to remove portions re mote from said contacting flats, milling said" tubes longitudinally to produce a fiat surfacej penpendicular to said contacting flats, slotting said tubes transversely through but for less than the entire width ofsaid-contacting flats, and se curing in the transverse slots of said tubes a plurality of steel plates with registering holes for engaging the joint-pins of the chain.

ERNEST ARTHUR DENN'ISQN. 1

40 5. In the manufactureof link chains, the method of fabricating a link-chain member by 

